All mood and no substance, “Before I Disappear” is Shawn Christensen’s feature-length expansion of his Academy Award-winning 19-minute film, “Curfew,” from 2012.

In this grungy atmospheric elaboration, set in Manhattan’s seedier environs, Richie (Mr. Christensen), a self-loathing loser who ekes out a living scrubbing toilets in a bowling alley, is about to kill himself when he receives a call from his bitter, estranged sister, Maggie (Emmy Rossum). She entreats him to look after her young daughter while she concludes some urgent, mysterious personal business. (We learn later that she has been arrested.)

Richie, who has slashed his wrists, steps out of the red bathtub water where he is waiting to die, slaps on a bandage and goes to meet his officious, intellectually precocious niece, Sophia (Fatima Ptacek). Accompanying her to school, he visits a class where this humorless, bossy little girl recites an Emily Dickinson poem in English and in Mandarin.

With no word from his sister, Richie drags Sophia on a surreal all-night tour of downscale locales that evokes a David Mamet play set in 1980s New York or Martin Scorsese’s “After Hours.” The movie’s liveliest moment is a fantasy sequence in the bowling alley in which Sophia leads a synchronized dance. But most of the additions to a short film that required no fleshing out contribute only half-baked plot complications involving assorted lowlifes.

As the initially contemptuous Sophia warms to her babysitter, “Before I Disappear” tries to pluck your heartstrings. But as an actor, Mr. Christensen, who wrote and directed the film, doesn’t have the requisite likability factor. Nor does Ms. Ptacek, who is too old for the role, which she also had in the short version.

Throughout the movie, you have the feeling of being dragged along on an impromptu journey by a filmmaker who is traveling without the benefit of a GPS device.

Written and directed by Shawn Christensen; director of photography, Daniel Katz; edited by Andrew Napier, Mr. Christensen and Damon Russell; music by Darren Morze; production design by Scott Kuzio; costumes by Kaela Wohl; produced by Mr. Christensen, Mr. Russell, Lucan Toh, Paul Wesley and Terry Leonard; released by IFC Films. Running time: 1 hour 33 minutes. This film is not rated.